check session before enabling join/create buttons

client/src/components/home/CreateGame.tsx

@@ -50,7 +50,12 @@ export default function CreateGame() {
           <option value="white">White</option>
           <option value="black">Black</option>
         </select>
-        <button className={"btn" + (buttonLoading ? " loading" : "")} type="submit">
+        <button
+          className={
+            "btn" + (buttonLoading ? " loading" : "") + (!session?.user?.id ? " btn-disabled" : "")
+          }
+          type="submit"
+        >
           Create
         </button>
       </div>

client/src/components/home/JoinGame.tsx

@@ -53,7 +53,14 @@ export default function JoinGame() {
         name="joinGameCode"
         id="joinGameCode"
       />
-      <button className={"btn btn-square" + (buttonLoading ? " loading" : "")} type="submit">
+      <button
+        className={
+          "btn btn-square" +
+          (buttonLoading ? " loading" : "") +
+          (!session?.user?.id ? " btn-disabled" : "")
+        }
+        type="submit"
+      >
         Join
       </button>
     </form>